The Prime Directive is one of those weird artifacts of the context of the original series. When naked imperialism was starting to be challeneged in pop culture but was still very much considered the status quo in the West, the idea not to interfere in other cultures was a bold stance. However, the idea of a "natural cultural progression" is unfortunately a product of its time and wasn't even something Kirk actually believed when it came down to it. Picard was more by the book but even he couldn't watch innocent people die when his crew pushed back. It's now pretty much universally regarded in canon as a stupid rule.